<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>我的网页</title>
</head>
<body>
    <!-- <>里面的叫做属性 -->
    <h1 align="center">一级标题</h1>
    <h2 align="left">二级标题</h2>
    <h3 align="right">三级标题</h3>
    <h4>四级标题</h4>
    <h5>五级标题</h5>
    <h6>六级标题</h6>
</body>
</html>